Hammer shears for rolled stock moving at high speed

ABSTRACT

A hammer shear assembly for severing fast moving tubular rolled stock has a plurality of at least three rolls each mounting an arcuate concave hammer knife, and drive means that drive the rolls in such timed relationship that all the knives will approximately simultaneously engage the rolled stock for severing.

United States Patent [72] Inventor Kurt W. Gruber Monchengladbach, Germany [21] Appl. No. 736,751

[22} Filed June 13, 1968 [45] Patented Jan. 19, 1971 [73] Assignee Mannesmann-Meer A. G.

Monchengladbach-Karmannsstrasse, Germany a corporation of Germany [32] Priority June13, 1967 [3 3 Germany [54] HAMMER SHEARS FOR ROLLED STOCK MOVING AT HIGH SPEED 6 Claims, 3 Drawing Figs.

[52] U.S.Cl. 83/310, 83/331, 83/444 [51] Int. Cl. B23d 25/12, B26d H56 [50] Field of Search [56] References Cited UNITED STATES PATENTS 2,033,967 1936 Yoder 83/436X 2,205,537 1940 Nye...... 83/339X 3,328,973 1967 Scheib 72/239 Primary Examiner-Andrew R. Juhasz Assistant Examiner.iames F. Coan Attorneys-Ernest F. Marmorek, Jordan B. Bierman and Marmorek and Bierman ABSTRACT: A hammer shear assembly for severing fast moving tubular rolled stockhas a plurality of at least three rolls each mounting an arcuate concave hammer knife, and drive means that drive the rolls in such timed relationship that all the knives will approximately simultaneously engage the rolled stock for severing.

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' PATENTEUJAu191s?! sumanFz lave- M HAMMER SI-IEARS FOR ROLLED STOCK MOVING AT HIGH SPEED The invention relates to the rolling of stock. and relates more particularly to the rolling of tubular stock. Still more particularly, the invention relates to shears for severing rolled tubular stock that moves at high speed.

During stretch reduction rolling of tubes, the exit speed of the hot tubular stock may reach up to 32.81 feet per second meters per second). In the endeavor to keep during rolling of tubular rolled stock the thickened ends at a minimum, although they cannot be avoided altogether. in modern rolling operations there have been introduced tubular strands of up to 328 feet (100 meters) length. Accordingly, during a sixfold or sevenfold stretching, the emerging strand will have about I968 feet (600 meters) to 2134 feet (700 meters), and the space as well as the conveyor equipment must be dimensioned to accommodate these lengths. Particular problems are, however, encountered due to these high exit speeds.

In order to meet these difficulties, the exiting tubular strand will be cut by suitable severing means, into individual tubular pieces, for instance into double commercial lengths of 67 feet (24 meters). This cutting takes place shortly after the stretch reduction rolling, by means of flying saws.

Flying saws are usable in connection with tubular rolled stock, for the exit speeds indicated in the foregoing. Where the exit speed is to be increased, however, flying saws are no longer suitable for the purpose of severing the tubular rolled stock. Yet, such increase in exit speeds is not only highly desirable, but also technically possible. The lack of suitable severing means, on the other hand, prevents the employment of increased speeds and their attendant advantages. The reasons why flying saws cannot be used in connection with rolled tubular stock of increased travelling speed, are the limit of the metal removal rate of the saw blade, on one hand, and on the other hand, the limit of the feeding speed of the saw, and due to the danger of explosion, the limit of rotational speed of the saw blade itself.

So-called hammer shears have been used for severing square stock and round stock. In hammer shears of this type, there is provided an upper knife rotating about its axis, and a lower knife rotating about its own axis, and conventional electronic control means are provided to adjust the hammer shears for desired cutting lengths, and the hammerlike strike effect of these knives results in a severance of the rolled stock in fractions of a second. Revolving hammer shears of this type, for use in severing solid sections, have been described in German patent Nos. 473,920,593588 and 1,022,879.

Attempts to utilize such hammer shears with opposite revolving knives for hollow sections have, however, not been successful. It has been found that the hollow cross sections were deformed, so that there occurred a great deal of waste, and the pieces needed to be subjected to additional milling operations.

It is accordingly among the principal objects of the invention to provide hammer shears for rolled tubular stock that moves at high speed, utilizing the advantages of hammer shears and at the same time avoiding the drawbacks experienced in their employment heretofore with hollow sections.

It is another object of the invention to provide hammer shears for the severing of rolled tubular stock emerging from the rolling mill at higher speeds than have heretofore been customary.

It is a further object of the invention to provide such hammer shears that in spite of the increased speed and the employment in connection with the severing of tubular rolled stock, will cut with precision and with little or no waste.

Further objects and advantages of the invention will be set forth in part in the following specification and in part will be obvious therefrom without being specifically referred to, the same being realized and attained as pointed out in the claims hereof.

Broadly speaking, the foregoing aims are accomplished in the instant invention by the provision of hammer shears that have a plurality of at least three rolls that define a circular passage for the moving rolled tubular stock, and each roll mounts a concavely arcuate hammer knife blade, and the rolls are driven in such timed relationship that all of the blades once during each revolution will be in position relative to each other to engage the rolled stock approximately simultaneously for cutting it and the rolls and knives will support the severed stock near its circumference.

With the above and other objects of the invention in view, the invention consists in the novel construction, arrangement and combination of various devices, elements and parts, as set forth in the claims hereof, one embodiment of the same being illustrated in the same being illustrated in the accompanying drawings and described in the specification.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description, taken in connection with the accompanying drawings, in which:

FIG. 1 is an end elevational view of a rolling frame, with rolls thereon, seen in the direction of travel of the rolled stock;

FIG. 2 is a fragmentary sectional view, taken on the line A-A of FIG. 1; and

FIG. 3 is an end elevational view, similar to FIG. I, but showing the rolling frame on a smaller scale and showing it built into a C-shaped roll housing.

In carrying the invention into effect in one of the embodiments which has been selected for illustration in the accompanying drawings and for description in this specification, and referring now particularly to FIG. 1, there are provided a plurality of at least three arcuate concave hammer knives 1. Each knife 1 is mounted on a roll 2, and all the rolls 2 are driven from a main shaft 4, over beveled gears 3. The rolls 2 that carry the knives 1 are mounted in one plane in a rolling frame 5.

In the exemplification of FIGS. 1-3, three rolls 2 are provided, and like wise three knives 1. As best shown in FIG. 1, the blades of the knives 1, when aligned, substantially complete an annular periphery, once during each revolution of the rolls 2. The drive means of the main shaft 4 and the gears 3 is so arranged that once during each revolution the knives 1 will be so positioned relative to each other to engage the rolled stock substantially simultaneously for severing it.

In operation, the hammer shears are actuated by the main shaft 4, the motor and brake arrangement of which is controlled electronically, in accordance with well-known conventional principles. The rolls 2 will be so rotated from the main shaft 4, that during an angle of rotation of about 270 of each roll, its peripheral speed will at the instant of cutting surpass the traveling speed of tubular rolled stock; this renders it possible that during the cutting itself the rolls 2 may be braked, and shortly after the emersion of the knives, the rolls 2 will be braked to standstill. The severing itself takes place throughout an angle of rotation of about 30.

In order to render the productivity of this equipment I economical, the necessary changes of a dimensional nature must be carried out as quickly as possible.

Due to the common driving means for all three rolls 2, it is possible, for instance as shown in FIG. 3, to utilize a conventional C-shaped roll housing 6, in which the rolling frame 5 that carries the rolls 2, can be mounted sidewardly rapidly, with the aid of a mounting table 7 and a conveyor 8.

I wish it to be understood that [do not desire to be lirnited t6 the exact details of construction shown and described, for obvious modifications will occur to a person skilled in the art.

For example, in the drawing there have been shown three rolls 2, and three knives l have been described. It will be understood, however, that the invention is not restricted to three knives; and a different plurality of knives I and rolls 2 may, accordingly, be utilized instead.

Having thus described the invention, what I claim as new and desire to be secured by Letters Patent, is as follows:

I claim:

1. Hammer shears. for use in severing tubular rolled stock moving at high speed in one direction. comprising in combination. at least three rolls defining a circular passage for said moving rolled stock. a concavely arcuate hammer knife blade mounted on each of said rolls. drive means operable for driving said rolls in such timed relationship that all of said blades once during each revolution will be so positioned relative to each other to engage the rolled stock substantially simultaneously for severing it, said rolls and knives being adapted to support said severed stock near its circumference.

2. Hammer shears as claimed in claim 1, said blades being operable to be aligned with each other, once during each revolution. in a plane substantially at right angles to said direction forming in said plane a substantially complete annu lar periphery.

3 Hammer shears, as claimed in claim 1. the axes of rotation of all of said rolls being disposed in one plane 4. Hammer shears, as claimed in claim 1. at least three rolls forming said plurality. each knife blade extending throughout an arc of substantially one-third of an annular periphery.

5. Hammer shears. as claimed in claim 1. said drive means including a main shaft and gearing rotating all said rolls at substantially the same angular speed.

6. Hammer shears, as claimed in claim 1, and a roll housing including a closed rolling frame mounting said knife carrying rolls and said drive means. 

1. Hammer shears, for use in severing tubular rolled stock moving at high speed in one direction, comprising in combination, at least three rolls defining a circular passage for said moving rolled stock, a concavely arcuate hammer knife blade mounted on each of said rolls, drive means operable for driving said rolls in such timed relationship that all of said blades once during each revolution will be so positioned relative to each other to engage the rolled stock substantially simultaneously for severing it, said rolls and knives being adapted to support said severed stock near its circumference.
 2. Hammer shears, as claimed in claim 1, said blades being operable to be aligned with each other, once during each revolution, in a plane substantially at right angles to said direction forming in said plane a substantially complete annular periphery.
 3. Hammer shears, as claimed in claim 1, the axes of rotation of all of said rolls being disposed in one plane.
 4. Hammer shears, as claimed in claim 1, at least three rolls forming said plurality, each knife blade extending throughout an arc of substantially one-third of an annular periphery.
 5. Hammer shears, as claimed in claim 1, said drive means including a main shaft and gearing rotating all said rolls at substantially the same angular speed.
 6. Hammer shears, as claimed in claim 1, and a roll housing including a closed rolling frame mounting said knife carrying rolls and said drive means. 